Mercurial > hg > octave-kai > gnulib-hg
annotate doc/regexprops-generic.texi @ 16416:7d97985fae86
Tests for module 'remainderl'.
* modules/remainderl-tests: New file.
* tests/test-remainderl.c: New file.
* tests/test-math-c++.cc: Check the declaration of remainderl.
| author | Bruno Haible <bruno@clisp.org> |
|---|---|
| date | Sat, 25 Feb 2012 20:40:44 +0100 |
| parents | 9e763e250026 |
| children | e542fd46ad6f |
| rev | line source |
|---|---|
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1 @c Copyright (C) 1994, 1996, 1998, 2000-2001, 2003-2007, 2009-2012 Free |
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2 @c Software Foundation, Inc. |
| 10095 | 3 @c |
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4 @c Permission is granted to copy, distribute and/or modify this document |
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5 @c under the terms of the GNU Free Documentation License, Version 1.3 or |
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6 @c any later version published by the Free Software Foundation; with no |
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7 @c Invariant Sections, with no Front-Cover Texts, and with no Back-Cover |
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8 @c Texts. A copy of the license is included in the ``GNU Free |
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9 @c Documentation License'' file as part of this distribution. |
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10 |
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11 @c this regular expression description is for: generic |
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12 |
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13 @menu |
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14 * awk regular expression syntax:: |
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15 * egrep regular expression syntax:: |
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16 * ed regular expression syntax:: |
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17 * emacs regular expression syntax:: |
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18 * gnu-awk regular expression syntax:: |
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19 * grep regular expression syntax:: |
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20 * posix-awk regular expression syntax:: |
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21 * posix-basic regular expression syntax:: |
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22 * posix-egrep regular expression syntax:: |
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23 * posix-extended regular expression syntax:: |
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24 * posix-minimal-basic regular expression syntax:: |
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25 * sed regular expression syntax:: |
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26 @end menu |
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27 |
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28 @node awk regular expression syntax |
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29 @subsection @samp{awk} regular expression syntax |
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30 |
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31 |
| 10095 | 32 The character @samp{.} matches any single character except the null character. |
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33 |
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34 |
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35 @table @samp |
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36 |
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37 @item + |
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39 @item ? |
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41 @item \+ |
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42 matches a @samp{+} |
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43 @item \? |
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45 @end table |
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46 |
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47 |
| 10095 | 48 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are invalid. Within square brackets, @samp{\} can be used to quote the following character. Character classes are not supported, so for example you would need to use @samp{[0-9]} instead of @samp{[[:digit:]]}. |
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49 |
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51 |
| 10095 | 52 Grouping is performed with parentheses @samp{()}. An unmatched @samp{)} matches just itself. A backslash followed by a digit matches that digit. |
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53 |
| 10095 | 54 The alternation operator is @samp{|}. |
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55 |
| 10095 | 56 The characters @samp{^} and @samp{$} always represent the beginning and end of a string respectively, except within square brackets. Within brackets, @samp{^} can be used to invert the membership of the character class being specified. |
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57 |
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58 @samp{*}, @samp{+} and @samp{?} are special at any point in a regular expression except: |
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59 @enumerate |
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60 |
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61 @item At the beginning of a regular expression |
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62 |
| 10095 | 63 @item After an open-group, signified by |
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64 @samp{(} |
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65 @item After the alternation operator @samp{|} |
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66 |
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67 @end enumerate |
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68 |
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69 |
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70 |
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71 |
| 10095 | 72 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
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73 |
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74 |
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75 @node egrep regular expression syntax |
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76 @subsection @samp{egrep} regular expression syntax |
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77 |
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78 |
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80 |
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81 |
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82 @table @samp |
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83 |
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84 @item + |
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86 @item ? |
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88 @item \+ |
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89 matches a @samp{+} |
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90 @item \? |
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92 @end table |
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93 |
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94 |
| 10095 | 95 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are ignored. Within square brackets, @samp{\} is taken literally. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. Non-matching lists @samp{[^@dots{}]} do not ever match newline. |
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96 |
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97 GNU extensions are supported: |
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98 @enumerate |
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99 |
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100 @item @samp{\w} matches a character within a word |
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101 |
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102 @item @samp{\W} matches a character which is not within a word |
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103 |
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104 @item @samp{\<} matches the beginning of a word |
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105 |
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106 @item @samp{\>} matches the end of a word |
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107 |
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108 @item @samp{\b} matches a word boundary |
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109 |
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110 @item @samp{\B} matches characters which are not a word boundary |
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111 |
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112 @item @samp{\`} matches the beginning of the whole input |
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113 |
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114 @item @samp{\'} matches the end of the whole input |
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115 |
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116 @end enumerate |
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117 |
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118 |
| 10095 | 119 Grouping is performed with parentheses @samp{()}. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{(}. |
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120 |
| 10095 | 121 The alternation operator is @samp{|}. |
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122 |
| 10095 | 123 The characters @samp{^} and @samp{$} always represent the beginning and end of a string respectively, except within square brackets. Within brackets, @samp{^} can be used to invert the membership of the character class being specified. |
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124 |
| 10095 | 125 The characters @samp{*}, @samp{+} and @samp{?} are special anywhere in a regular expression. |
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126 |
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127 |
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128 |
| 10095 | 129 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
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130 |
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131 |
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132 @node ed regular expression syntax |
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133 @subsection @samp{ed} regular expression syntax |
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134 |
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135 |
| 10095 | 136 The character @samp{.} matches any single character except the null character. |
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137 |
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138 |
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139 @table @samp |
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140 |
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141 @item \+ |
| 10095 | 142 indicates that the regular expression should match one or more occurrences of the previous atom or regexp. |
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143 @item \? |
| 10095 | 144 indicates that the regular expression should match zero or one occurrence of the previous atom or regexp. |
| 145 @item + and ? | |
| 146 match themselves. | |
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147 @end table |
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148 |
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149 |
| 10095 | 150 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are invalid. Within square brackets, @samp{\} is taken literally. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. |
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151 |
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152 GNU extensions are supported: |
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153 @enumerate |
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154 |
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155 @item @samp{\w} matches a character within a word |
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156 |
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157 @item @samp{\W} matches a character which is not within a word |
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158 |
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159 @item @samp{\<} matches the beginning of a word |
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160 |
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161 @item @samp{\>} matches the end of a word |
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162 |
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163 @item @samp{\b} matches a word boundary |
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164 |
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165 @item @samp{\B} matches characters which are not a word boundary |
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166 |
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167 @item @samp{\`} matches the beginning of the whole input |
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168 |
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169 @item @samp{\'} matches the end of the whole input |
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170 |
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171 @end enumerate |
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172 |
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173 |
| 10095 | 174 Grouping is performed with backslashes followed by parentheses @samp{\(}, @samp{\)}. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{\(}. |
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175 |
| 10095 | 176 The alternation operator is @samp{\|}. |
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177 |
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178 The character @samp{^} only represents the beginning of a string when it appears: |
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179 @enumerate |
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180 |
| 10095 | 181 @item |
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182 At the beginning of a regular expression |
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183 |
| 10095 | 184 @item After an open-group, signified by |
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185 @samp{\(} |
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186 |
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187 @item After the alternation operator @samp{\|} |
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188 |
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189 @end enumerate |
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190 |
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191 |
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192 The character @samp{$} only represents the end of a string when it appears: |
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193 @enumerate |
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194 |
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195 @item At the end of a regular expression |
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196 |
| 10095 | 197 @item Before a close-group, signified by |
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198 @samp{\)} |
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199 @item Before the alternation operator @samp{\|} |
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200 |
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201 @end enumerate |
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202 |
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203 |
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204 @samp{\*}, @samp{\+} and @samp{\?} are special at any point in a regular expression except: |
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205 @enumerate |
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206 |
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207 @item At the beginning of a regular expression |
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208 |
| 10095 | 209 @item After an open-group, signified by |
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210 @samp{\(} |
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211 @item After the alternation operator @samp{\|} |
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212 |
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213 @end enumerate |
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214 |
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215 |
| 10095 | 216 Intervals are specified by @samp{\@{} and @samp{\@}}. Invalid intervals such as @samp{a\@{1z} are not accepted. |
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217 |
| 10095 | 218 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
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219 |
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220 |
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221 @node emacs regular expression syntax |
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222 @subsection @samp{emacs} regular expression syntax |
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223 |
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224 |
| 10095 | 225 The character @samp{.} matches any single character except newline. |
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226 |
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227 |
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228 @table @samp |
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229 |
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230 @item + |
| 10095 | 231 indicates that the regular expression should match one or more occurrences of the previous atom or regexp. |
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232 @item ? |
| 10095 | 233 indicates that the regular expression should match zero or one occurrence of the previous atom or regexp. |
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234 @item \+ |
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235 matches a @samp{+} |
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236 @item \? |
| 10095 | 237 matches a @samp{?}. |
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238 @end table |
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239 |
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240 |
| 10095 | 241 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are ignored. Within square brackets, @samp{\} is taken literally. Character classes are not supported, so for example you would need to use @samp{[0-9]} instead of @samp{[[:digit:]]}. |
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242 |
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243 GNU extensions are supported: |
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244 @enumerate |
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245 |
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246 @item @samp{\w} matches a character within a word |
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247 |
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248 @item @samp{\W} matches a character which is not within a word |
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249 |
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250 @item @samp{\<} matches the beginning of a word |
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251 |
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252 @item @samp{\>} matches the end of a word |
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253 |
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254 @item @samp{\b} matches a word boundary |
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255 |
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256 @item @samp{\B} matches characters which are not a word boundary |
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257 |
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258 @item @samp{\`} matches the beginning of the whole input |
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259 |
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260 @item @samp{\'} matches the end of the whole input |
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261 |
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262 @end enumerate |
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263 |
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264 |
| 10095 | 265 Grouping is performed with backslashes followed by parentheses @samp{\(}, @samp{\)}. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{\(}. |
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266 |
| 10095 | 267 The alternation operator is @samp{\|}. |
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268 |
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269 The character @samp{^} only represents the beginning of a string when it appears: |
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270 @enumerate |
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271 |
| 10095 | 272 @item |
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273 At the beginning of a regular expression |
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274 |
| 10095 | 275 @item After an open-group, signified by |
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276 @samp{\(} |
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277 |
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278 @item After the alternation operator @samp{\|} |
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279 |
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280 @end enumerate |
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281 |
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282 |
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283 The character @samp{$} only represents the end of a string when it appears: |
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284 @enumerate |
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285 |
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286 @item At the end of a regular expression |
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287 |
| 10095 | 288 @item Before a close-group, signified by |
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289 @samp{\)} |
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290 @item Before the alternation operator @samp{\|} |
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291 |
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292 @end enumerate |
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293 |
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294 |
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295 @samp{*}, @samp{+} and @samp{?} are special at any point in a regular expression except: |
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296 @enumerate |
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297 |
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298 @item At the beginning of a regular expression |
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299 |
| 10095 | 300 @item After an open-group, signified by |
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301 @samp{\(} |
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302 @item After the alternation operator @samp{\|} |
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303 |
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304 @end enumerate |
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305 |
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306 |
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307 |
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308 |
| 10095 | 309 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
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310 |
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311 |
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312 @node gnu-awk regular expression syntax |
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313 @subsection @samp{gnu-awk} regular expression syntax |
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314 |
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315 |
| 10095 | 316 The character @samp{.} matches any single character. |
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317 |
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318 |
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319 @table @samp |
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320 |
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321 @item + |
| 10095 | 322 indicates that the regular expression should match one or more occurrences of the previous atom or regexp. |
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323 @item ? |
| 10095 | 324 indicates that the regular expression should match zero or one occurrence of the previous atom or regexp. |
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325 @item \+ |
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326 matches a @samp{+} |
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327 @item \? |
| 10095 | 328 matches a @samp{?}. |
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329 @end table |
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330 |
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331 |
| 10095 | 332 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are invalid. Within square brackets, @samp{\} can be used to quote the following character. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. |
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333 |
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334 GNU extensions are supported: |
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335 @enumerate |
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336 |
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337 @item @samp{\w} matches a character within a word |
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338 |
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339 @item @samp{\W} matches a character which is not within a word |
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340 |
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341 @item @samp{\<} matches the beginning of a word |
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342 |
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343 @item @samp{\>} matches the end of a word |
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344 |
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345 @item @samp{\b} matches a word boundary |
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346 |
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347 @item @samp{\B} matches characters which are not a word boundary |
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348 |
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349 @item @samp{\`} matches the beginning of the whole input |
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350 |
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351 @item @samp{\'} matches the end of the whole input |
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352 |
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353 @end enumerate |
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354 |
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355 |
| 10095 | 356 Grouping is performed with parentheses @samp{()}. An unmatched @samp{)} matches just itself. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{(}. |
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357 |
| 10095 | 358 The alternation operator is @samp{|}. |
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359 |
| 10095 | 360 The characters @samp{^} and @samp{$} always represent the beginning and end of a string respectively, except within square brackets. Within brackets, @samp{^} can be used to invert the membership of the character class being specified. |
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361 |
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362 @samp{*}, @samp{+} and @samp{?} are special at any point in a regular expression except: |
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363 @enumerate |
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364 |
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365 @item At the beginning of a regular expression |
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366 |
| 10095 | 367 @item After an open-group, signified by |
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368 @samp{(} |
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369 @item After the alternation operator @samp{|} |
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370 |
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371 @end enumerate |
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372 |
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373 |
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374 |
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375 |
| 10095 | 376 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
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377 |
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378 |
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379 @node grep regular expression syntax |
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380 @subsection @samp{grep} regular expression syntax |
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381 |
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382 |
| 10095 | 383 The character @samp{.} matches any single character except newline. |
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384 |
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385 |
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386 @table @samp |
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387 |
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388 @item \+ |
| 10095 | 389 indicates that the regular expression should match one or more occurrences of the previous atom or regexp. |
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390 @item \? |
| 10095 | 391 indicates that the regular expression should match zero or one occurrence of the previous atom or regexp. |
| 392 @item + and ? | |
| 393 match themselves. | |
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394 @end table |
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395 |
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396 |
| 10095 | 397 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are ignored. Within square brackets, @samp{\} is taken literally. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. Non-matching lists @samp{[^@dots{}]} do not ever match newline. |
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398 |
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399 GNU extensions are supported: |
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400 @enumerate |
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401 |
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402 @item @samp{\w} matches a character within a word |
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403 |
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404 @item @samp{\W} matches a character which is not within a word |
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405 |
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406 @item @samp{\<} matches the beginning of a word |
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407 |
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408 @item @samp{\>} matches the end of a word |
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409 |
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410 @item @samp{\b} matches a word boundary |
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411 |
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412 @item @samp{\B} matches characters which are not a word boundary |
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413 |
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414 @item @samp{\`} matches the beginning of the whole input |
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415 |
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416 @item @samp{\'} matches the end of the whole input |
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417 |
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418 @end enumerate |
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419 |
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420 |
| 10095 | 421 Grouping is performed with backslashes followed by parentheses @samp{\(}, @samp{\)}. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{\(}. |
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422 |
| 10095 | 423 The alternation operator is @samp{\|}. |
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424 |
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425 The character @samp{^} only represents the beginning of a string when it appears: |
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426 @enumerate |
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427 |
| 10095 | 428 @item |
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429 At the beginning of a regular expression |
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430 |
| 10095 | 431 @item After an open-group, signified by |
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432 @samp{\(} |
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433 |
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434 @item After a newline |
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435 |
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436 @item After the alternation operator @samp{\|} |
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437 |
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438 @end enumerate |
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439 |
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440 |
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441 The character @samp{$} only represents the end of a string when it appears: |
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442 @enumerate |
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443 |
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444 @item At the end of a regular expression |
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445 |
| 10095 | 446 @item Before a close-group, signified by |
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447 @samp{\)} |
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448 @item Before a newline |
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449 |
|
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450 @item Before the alternation operator @samp{\|} |
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451 |
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452 @end enumerate |
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453 |
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454 |
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455 @samp{\*}, @samp{\+} and @samp{\?} are special at any point in a regular expression except: |
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456 @enumerate |
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457 |
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458 @item At the beginning of a regular expression |
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459 |
| 10095 | 460 @item After an open-group, signified by |
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461 @samp{\(} |
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462 @item After a newline |
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463 |
|
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464 @item After the alternation operator @samp{\|} |
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465 |
|
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466 @end enumerate |
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467 |
|
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468 |
| 10095 | 469 Intervals are specified by @samp{\@{} and @samp{\@}}. Invalid intervals such as @samp{a\@{1z} are not accepted. |
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470 |
| 10095 | 471 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
|
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472 |
|
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473 |
|
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474 @node posix-awk regular expression syntax |
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475 @subsection @samp{posix-awk} regular expression syntax |
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476 |
|
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477 |
| 10095 | 478 The character @samp{.} matches any single character except the null character. |
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479 |
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|
480 |
|
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481 @table @samp |
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482 |
|
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483 @item + |
| 10095 | 484 indicates that the regular expression should match one or more occurrences of the previous atom or regexp. |
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485 @item ? |
| 10095 | 486 indicates that the regular expression should match zero or one occurrence of the previous atom or regexp. |
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487 @item \+ |
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488 matches a @samp{+} |
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489 @item \? |
| 10095 | 490 matches a @samp{?}. |
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491 @end table |
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492 |
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493 |
| 10095 | 494 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are invalid. Within square brackets, @samp{\} can be used to quote the following character. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. |
|
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495 |
| 10095 | 496 GNU extensions are not supported and so @samp{\w}, @samp{\W}, @samp{\<}, @samp{\>}, @samp{\b}, @samp{\B}, @samp{\`}, and @samp{\'} match @samp{w}, @samp{W}, @samp{<}, @samp{>}, @samp{b}, @samp{B}, @samp{`}, and @samp{'} respectively. |
|
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497 |
| 10095 | 498 Grouping is performed with parentheses @samp{()}. An unmatched @samp{)} matches just itself. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{(}. |
|
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499 |
| 10095 | 500 The alternation operator is @samp{|}. |
|
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501 |
| 10095 | 502 The characters @samp{^} and @samp{$} always represent the beginning and end of a string respectively, except within square brackets. Within brackets, @samp{^} can be used to invert the membership of the character class being specified. |
|
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503 |
|
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* doc/regexprops-generic.texi: change "an close-group" to "a
James Youngman <jay@gnu.org>
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7146
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504 @samp{*}, @samp{+} and @samp{?} are special at any point in a regular expression except the following places, where they are not allowed: |
|
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505 @enumerate |
|
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Karl Berry <karl@freefriends.org>
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506 |
|
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507 @item At the beginning of a regular expression |
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508 |
| 10095 | 509 @item After an open-group, signified by |
|
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510 @samp{(} |
|
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511 @item After the alternation operator @samp{|} |
|
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512 |
|
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513 @end enumerate |
|
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514 |
|
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515 |
| 10095 | 516 Intervals are specified by @samp{@{} and @samp{@}}. Invalid intervals such as @samp{a@{1z} are not accepted. |
|
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517 |
| 10095 | 518 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
|
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519 |
|
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|
520 |
|
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521 @node posix-basic regular expression syntax |
|
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Karl Berry <karl@freefriends.org>
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|
522 @subsection @samp{posix-basic} regular expression syntax |
|
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Karl Berry <karl@freefriends.org>
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523 This is a synonym for ed. |
|
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524 @node posix-egrep regular expression syntax |
|
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Karl Berry <karl@freefriends.org>
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525 @subsection @samp{posix-egrep} regular expression syntax |
|
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|
526 |
|
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|
527 |
| 10095 | 528 The character @samp{.} matches any single character except newline. |
|
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|
529 |
|
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Karl Berry <karl@freefriends.org>
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|
530 |
|
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Karl Berry <karl@freefriends.org>
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|
531 @table @samp |
|
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Karl Berry <karl@freefriends.org>
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|
532 |
|
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|
533 @item + |
| 10095 | 534 indicates that the regular expression should match one or more occurrences of the previous atom or regexp. |
|
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535 @item ? |
| 10095 | 536 indicates that the regular expression should match zero or one occurrence of the previous atom or regexp. |
|
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537 @item \+ |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
538 matches a @samp{+} |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
539 @item \? |
| 10095 | 540 matches a @samp{?}. |
|
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|
541 @end table |
|
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Karl Berry <karl@freefriends.org>
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|
542 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
543 |
| 10095 | 544 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are ignored. Within square brackets, @samp{\} is taken literally. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. Non-matching lists @samp{[^@dots{}]} do not ever match newline. |
|
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|
545 |
|
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Karl Berry <karl@freefriends.org>
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|
546 GNU extensions are supported: |
|
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|
547 @enumerate |
|
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|
548 |
|
47323bc9321f
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parents:
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|
549 @item @samp{\w} matches a character within a word |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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diff
changeset
|
550 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
551 @item @samp{\W} matches a character which is not within a word |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
552 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
553 @item @samp{\<} matches the beginning of a word |
|
47323bc9321f
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parents:
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|
554 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
555 @item @samp{\>} matches the end of a word |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
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|
556 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
557 @item @samp{\b} matches a word boundary |
|
47323bc9321f
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|
558 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
559 @item @samp{\B} matches characters which are not a word boundary |
|
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|
560 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
561 @item @samp{\`} matches the beginning of the whole input |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
diff
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|
562 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
563 @item @samp{\'} matches the end of the whole input |
|
47323bc9321f
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parents:
diff
changeset
|
564 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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diff
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|
565 @end enumerate |
|
47323bc9321f
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|
566 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
567 |
| 10095 | 568 Grouping is performed with parentheses @samp{()}. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{(}. |
|
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parents:
diff
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|
569 |
| 10095 | 570 The alternation operator is @samp{|}. |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
571 |
| 10095 | 572 The characters @samp{^} and @samp{$} always represent the beginning and end of a string respectively, except within square brackets. Within brackets, @samp{^} can be used to invert the membership of the character class being specified. |
|
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Karl Berry <karl@freefriends.org>
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|
573 |
| 10095 | 574 The characters @samp{*}, @samp{+} and @samp{?} are special anywhere in a regular expression. |
|
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diff
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|
575 |
|
47323bc9321f
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diff
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|
576 Intervals are specified by @samp{@{} and @samp{@}}. Invalid intervals are treated as literals, for example @samp{a@{1} is treated as @samp{a\@{1} |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
577 |
| 10095 | 578 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
|
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Karl Berry <karl@freefriends.org>
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|
579 |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
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|
580 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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diff
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|
581 @node posix-extended regular expression syntax |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
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|
582 @subsection @samp{posix-extended} regular expression syntax |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
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|
583 |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
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|
584 |
| 10095 | 585 The character @samp{.} matches any single character except the null character. |
|
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Karl Berry <karl@freefriends.org>
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|
586 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
587 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
588 @table @samp |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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589 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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590 @item + |
| 10095 | 591 indicates that the regular expression should match one or more occurrences of the previous atom or regexp. |
|
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Karl Berry <karl@freefriends.org>
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592 @item ? |
| 10095 | 593 indicates that the regular expression should match zero or one occurrence of the previous atom or regexp. |
|
6008
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Karl Berry <karl@freefriends.org>
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594 @item \+ |
|
47323bc9321f
regexprops, generated by findutils helper
Karl Berry <karl@freefriends.org>
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|
595 matches a @samp{+} |
|
47323bc9321f
regexprops, generated by findutils helper
Karl Berry <karl@freefriends.org>
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changeset
|
596 @item \? |
| 10095 | 597 matches a @samp{?}. |
|
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|
598 @end table |
|
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|
599 |
|
47323bc9321f
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parents:
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changeset
|
600 |
| 10095 | 601 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are invalid. Within square brackets, @samp{\} is taken literally. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. |
|
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|
602 |
|
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parents:
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|
603 GNU extensions are supported: |
|
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parents:
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604 @enumerate |
|
47323bc9321f
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parents:
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605 |
|
47323bc9321f
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606 @item @samp{\w} matches a character within a word |
|
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Karl Berry <karl@freefriends.org>
parents:
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changeset
|
607 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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608 @item @samp{\W} matches a character which is not within a word |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
changeset
|
609 |
|
47323bc9321f
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parents:
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changeset
|
610 @item @samp{\<} matches the beginning of a word |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
611 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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612 @item @samp{\>} matches the end of a word |
|
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parents:
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|
613 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
614 @item @samp{\b} matches a word boundary |
|
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Karl Berry <karl@freefriends.org>
parents:
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changeset
|
615 |
|
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Karl Berry <karl@freefriends.org>
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616 @item @samp{\B} matches characters which are not a word boundary |
|
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617 |
|
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Karl Berry <karl@freefriends.org>
parents:
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618 @item @samp{\`} matches the beginning of the whole input |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
619 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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620 @item @samp{\'} matches the end of the whole input |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
621 |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
622 @end enumerate |
|
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Karl Berry <karl@freefriends.org>
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|
623 |
|
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Karl Berry <karl@freefriends.org>
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624 |
| 10095 | 625 Grouping is performed with parentheses @samp{()}. An unmatched @samp{)} matches just itself. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{(}. |
|
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Karl Berry <karl@freefriends.org>
parents:
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626 |
| 10095 | 627 The alternation operator is @samp{|}. |
|
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|
628 |
| 10095 | 629 The characters @samp{^} and @samp{$} always represent the beginning and end of a string respectively, except within square brackets. Within brackets, @samp{^} can be used to invert the membership of the character class being specified. |
|
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630 |
|
9500
4c535eec83bd
* doc/regexprops-generic.texi: change "an close-group" to "a
James Youngman <jay@gnu.org>
parents:
7146
diff
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|
631 @samp{*}, @samp{+} and @samp{?} are special at any point in a regular expression except the following places, where they are not allowed: |
|
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Karl Berry <karl@freefriends.org>
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632 @enumerate |
|
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Karl Berry <karl@freefriends.org>
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633 |
|
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Karl Berry <karl@freefriends.org>
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634 @item At the beginning of a regular expression |
|
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Karl Berry <karl@freefriends.org>
parents:
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635 |
| 10095 | 636 @item After an open-group, signified by |
|
6008
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Karl Berry <karl@freefriends.org>
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|
637 @samp{(} |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
638 @item After the alternation operator @samp{|} |
|
47323bc9321f
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|
639 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
640 @end enumerate |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
641 |
|
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Karl Berry <karl@freefriends.org>
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|
642 |
| 10095 | 643 Intervals are specified by @samp{@{} and @samp{@}}. Invalid intervals such as @samp{a@{1z} are not accepted. |
|
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parents:
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644 |
| 10095 | 645 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
|
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|
646 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
647 |
|
47323bc9321f
regexprops, generated by findutils helper
Karl Berry <karl@freefriends.org>
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|
648 @node posix-minimal-basic regular expression syntax |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
649 @subsection @samp{posix-minimal-basic} regular expression syntax |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
650 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
651 |
| 10095 | 652 The character @samp{.} matches any single character except the null character. |
|
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Karl Berry <karl@freefriends.org>
parents:
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653 |
|
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Karl Berry <karl@freefriends.org>
parents:
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changeset
|
654 |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
changeset
|
655 |
| 10095 | 656 Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example @samp{[z-a]}, are invalid. Within square brackets, @samp{\} is taken literally. Character classes are supported; for example @samp{[[:digit:]]} will match a single decimal digit. |
|
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Karl Berry <karl@freefriends.org>
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657 |
|
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658 GNU extensions are supported: |
|
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parents:
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|
659 @enumerate |
|
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|
660 |
|
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|
661 @item @samp{\w} matches a character within a word |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
662 |
|
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663 @item @samp{\W} matches a character which is not within a word |
|
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|
664 |
|
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Karl Berry <karl@freefriends.org>
parents:
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665 @item @samp{\<} matches the beginning of a word |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
666 |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
667 @item @samp{\>} matches the end of a word |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
668 |
|
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parents:
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|
669 @item @samp{\b} matches a word boundary |
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Karl Berry <karl@freefriends.org>
parents:
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|
670 |
|
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parents:
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|
671 @item @samp{\B} matches characters which are not a word boundary |
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Karl Berry <karl@freefriends.org>
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|
672 |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
673 @item @samp{\`} matches the beginning of the whole input |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
674 |
|
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Karl Berry <karl@freefriends.org>
parents:
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changeset
|
675 @item @samp{\'} matches the end of the whole input |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
676 |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
677 @end enumerate |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
678 |
|
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Karl Berry <karl@freefriends.org>
parents:
diff
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|
679 |
| 10095 | 680 Grouping is performed with backslashes followed by parentheses @samp{\(}, @samp{\)}. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example @samp{\2} matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis @samp{\(}. |
|
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|
681 |
|
47323bc9321f
regexprops, generated by findutils helper
Karl Berry <karl@freefriends.org>
parents:
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|
682 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
683 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
684 The character @samp{^} only represents the beginning of a string when it appears: |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
685 @enumerate |
|
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Karl Berry <karl@freefriends.org>
parents:
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|
686 |
| 10095 | 687 @item |
|
6008
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|
688 At the beginning of a regular expression |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
689 |
| 10095 | 690 @item After an open-group, signified by |
|
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|
691 @samp{\(} |
|
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parents:
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changeset
|
692 |
|
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|
693 @end enumerate |
|
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|
694 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
695 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
696 The character @samp{$} only represents the end of a string when it appears: |
|
47323bc9321f
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|
697 @enumerate |
|
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|
698 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
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|
699 @item At the end of a regular expression |
|
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parents:
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|
700 |
| 10095 | 701 @item Before a close-group, signified by |
|
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|
702 @samp{\)} |
|
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|
703 @end enumerate |
|
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parents:
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|
704 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
705 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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changeset
|
706 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
707 |
| 10095 | 708 Intervals are specified by @samp{\@{} and @samp{\@}}. Invalid intervals such as @samp{a\@{1z} are not accepted. |
|
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|
709 |
| 10095 | 710 The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups. |
|
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|
711 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
712 |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
713 @node sed regular expression syntax |
|
47323bc9321f
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Karl Berry <karl@freefriends.org>
parents:
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|
714 @subsection @samp{sed} regular expression syntax |
|
16297
9e763e250026
maint: remove empty lines at EOF, but excluding modules/*
Jim Meyering <meyering@redhat.com>
parents:
16201
diff
changeset
|
715 This is a synonym for ed. |